Tree rings may underestimate climate response to volcanic eruptions

UNIVERSITY PARK, Pa. -- Some climate cooling caused by past volcanic eruptions may not be evident in tree-ring reconstructions of temperature change, because large enough temperature drops lead to greatly shortened or even absent growing seasons, according to climate researchers who compared tree-ring temperature reconstructions with model simulations of past temperature changes.

Tree rings are used as proxies for climate because trees create unique rings
each year that often reflect the weather conditions that influenced the growing
season that year. For reconstructing climate conditions, tree-ring researchers
seek trees growing at the extremes of their growth range. Inferring temperature
changes required going to locations either at the tree line caused by elevation
or at the boreal tree line, the northern-most place where the trees will
grow.